W124 Rotor Replacement
 

Although the DIY instructions on this web site are very good, there are some details to add for rotor replacement. I have a 1994 E320 Wagon with 89,000 miles. I replaced all 4 rotors and pads. My model has ASR. I ordered all parts from FastLane (thanks, Phil) but they were out of PBR Deluxe pads so I got Mintex on the front and Textar yellow box on the rears.[list=1][*]Checking that the rotor is flat - the instructions that came with the Balo rotors say to check them with a runout gauge after installation. I do not think a DIYer can or should do this since until the wheel is tightened up it is likely the rotor will not appear exactly flat on runout. I would say if using new rotors of good quality do not bother with this[*]Rear Rotors incorporate a parking brake. For some reason the rear rotors were much harder to break free than the front. In the process of doing so one of the parking brake pads broke up. I would in the future just buy new parking brake pads and replace them as part of the job. Now I have to do it again next weekend![*]Realize that with ASR there are 8 total pad sensors to be replaced. Phil only shipped 4 (even though I told him it had ASR). Sensors are $8 EACH at the dealer, whereas Phil's are less than $2.[*]The rear pads incorporated a shim which "inserted" into a recess in the caliper which was very difficult to remove. I had to break them apart to get them out. My new pads did not fit properly with those shims in place.[/list=1]

Let me know how you like the pads. I just changed mine to Axxis Deluxe Plus pads and so far so good. Will report back after I have more usage on them.

You should thoroughly steel brush the flat hub surface against which the rotor mounts. If you do this, you shouldn't have to worry about runout.

The easiest way to do this is after removing the bearings and seal from the hub for cleaning before repacking, clean the hub to get all the old grease out and then dry. After drying, take it to the steel brush on the bench grinder and clean the flat surface THOROUGHLY until it shines.

If you don't have a bench grinder, use a handheld steel brush, or a steel brush on a drill motor. After this step, rewash the hub internals to ensure that you have not left any steel brush fibers in there to spoil your wheel bearings.

Good luck,

And to keep from breaking the parking brake shoes simply back them off until the rear rotor slips off easily. Yours were likely adjusted to close spec, which causes the shoe to catch inside the parking brake drum.

Presuming your brakes are similar to mine...

Yeah, those rear pad backing shims did not fit for me with the PBR pads either. Just as well, they were deteriorated.

The rear rotors will hang on the parking brake if the lever that actuates them is frozen (like one of mine was). Not anything to be done about it that I can think of, since the adjustors are not accessible from the back, as they are on many other cars.
They dig themselves a groove over time, and catch on the ridge. Ah, the joys of drum brakes...

I would hope that you would not need to test new rotors for runout. Never observed such a problem.

Access to the adjuster should be though one of the lug bolt holes, I think situated at about 1 o'clock.

It will be 1 o'clock on the right side and 11 o'clock on the left side. In other words, slightly forward from the top.

Good luck,

Lug bolt hole, eh? Thanks guys. Interesting trick. I suppose I should RTFM, though it did not matter in my case, since I intended to replace the parking brake components anyways.

Perhaps that will help ChipJ too.

Yes it will help me NEXT time!
 

What is done on the SAABNET board is for some of these common procedures people gather up all their experience and post it in the FAQ under one subject - for example, in this case, brake service. Has anyone considered doing that on this board?

That all makes sense about the rotor and the parking brake by the way. The inside of my rotor was a rusty hellhole. I can't believe the parking brake still worked (although it works less well now).